This paper focuses on the impact of fee arrangement on the amount of time lawyers are likely to devote to civil cases ("effort"). Drawing on data collected by the Civil Litigation Research Project, the authors compare the behavior of lawyers working on an hourly fee basis with the behavior of contingent fee lawyers. Like previous work on this issue, the paper finds that fee arrangement does influence the amount of effort lawyers devote to a given case. However, contrary to previous work, the analysis indicates that the impact is not a simple one on hours worked; there is a more complex effect on a number of aspects of lawyers' behavior. Together these produce an effect on hours that varies by size of case. For modest cases (with stakes of $6000 or less), contingent fee lawyers spend less time on a case than hourly fee lawyers. Yet the authors find no statistically significant evidence of a differential in effort for larger cases but rather an indication that, if there is an effect, it may be in the opposite direction.